Electrical cable and a method of making the same



Nov. 2, 1937. L o. REICHEL-r 2,097,50 l ELECTRICAL. CABLE Ann A nm'ruonoF mine THE SAME Filed July 12, 1933 e sheets-sheet 1 f l l/ l 'n (D 1 vP Y' l l i A N f- 3 l l' |,1 .ML |I I 'l Il n f'\.. V k N -I v l u I u lN Il 'f Q I I n /NvENroR u -L. o. RE/cf/ELT v s sr 4 R mmh...

A TTORNEY -Nov. 2, 1937. 0* RE|HELT L2,097,501

ELECTRICAL CABLE AND A METHOD OF MAKING THE SAME Filed July l, 1933 esheets-sheet 2 FIG. J

A Jim1.'

ill INYIIIIIIIIIIIIIIIIIIIW FIG. d. FIG.9 FIG. I0

/NvE/vron L. O. RE/CHELT 4 r ro RNE r Nov. 2, 1937. 1 o. RE|HLT'2,097,501

ELECTRICAL CABLE AND A ETI-10D 0F MAKING THE SAMEV Filed July 12, 1933 6Sheets-Sheet 3 /N vE/v ron L. o. @tlc/161.7'

A TTORNE'Y Nov. 2, 1937. L Q RHCHELT 2,097,501

lELECTRIC@ CABLE AND A lETHoD or' MAKING'THE SAME .Filed July 12, 193:5e sheets-sheet 4 ATTORNEY Nov. 2,Y 1937. 1 Q RElCHELT 2,097,501

ELECTRICAL CABLE AND A IETHOD OF IAKING THE SABE Filed July 12, 1933 6Sheets-Sheet 5 FIG. 20

mw .Luvulnmlul FIG'. 5 43 /lo -l1-MM .L 1" i mmm l r nanas F1622?. r/s.za

[2l `r`l20 ne. .n Q gill' Flc. 32

INI/wrok jmmm' Mu a' 1.. o. Avr/cnn r AYE` A TTORNEY Nov. 2, 1937. L QRElcHELT 2,097,501

ELECTRICAL CABLE AND A METHOD OF IAKING'THE SAIE Filed July 12, 1933 6Sheets-Sheet 6 N a s FIG. J4

Patented Nov, 2, 1937 PATENT OFFICE ELECTRICAL CABLE AND A METHOD OFMAKING THE' SAME Lester O. Reichelt, Cranford, N. J., assignor toWestern Electric Company, Incorporated, New York, N. Y., a corporationof New York Application .my 12, 193s, semi No. 680,037

6 Claims.

The invention relates to electrical cables and a method of and apparatusfor making the same, and more particularly to multi-conductor cablesoi.' the type employed for the transmission of intelligenceelectrically.

Objects o! the present invention are to im-.

prove the construction and provide an improved method and improvedapparatus for constructing the cable. lo In accordance with a preferredembodiment o! the invention there is applied over a cable core having astrand binding, a crinkled or crepe paper covering freely .expansible ina longitudinal direction, and sell' adaptable to helical formations oi'the cable core. The paper covering comprises one or more strips of crepepaper applied longitudinally with the cable core and wrappedtransversely around the cable coreby means of one or more dies so thatthe paper covering completely encircles the cable core, and in the caseof cables having a metal sheath extruded or otherwise formed over thepaper covered core, the crinkled paper forms a cushioning pad betweenthe conductors and the sheath eilective to protect the conductors fromwrinkles on the inner surface of the metal sheath formed when the cableis bent.

In two preferred embodiments herein shown and described the paper isapplied over the cable core just prior to the application of a metallicsheath and in another preferred embodiment the paper is applied at thesame time that the stranding oi the insulating conductors into a core'takes place. In this embodiment the paper strips are longitudinallyspiralled around the core due to the twisting of the core in thestranding operation and a strand binding is applied thereover to causethe paperto completely encircle the core and to retain the paper on thecore. o 'I'he invention will be better. understood from `the followingdetailed description and accornpanying drawings, in which Fig. 1 is aview, partially in section, oi one embodiment of the invention; l

4,5 Fig. 2 is an enlarged view, partially in section, of a portion ofthe apparatus shown in Fig. l, taken along the line 2-2 of Fig. l;

Fig. 3 is a plan view of a paper forming die; Fig. 4 is a. section alongthe line 4 4 of Fig. 3; Fig. 5 is a section along the line 5 5 of Fig.3; Fig. 6 is an enlarged view, partially in section, of one end of thepaper forming die shown in Fis. 3;

Fig. 7 is another type oi paper forming die; 66 Fig. 8 is an enlargedview, partially in section of one end of the moisture proof tube shownin Fig. 1 for conveying the cable and paper to the paper forming die;

Fig. 9 is a cross-section of the end of the moisture prooi' tube shownin Fig. 10; 5 Fig. 10 is an enlarged view of the other end of themoisture proof tube shown in Figs. 1 and 8;

Fig. 11 is a view of a cable showing the method of application o1' thepaper longitudinally over the cable core; 10

Figs. 12, 13, and 14 are sectional views o1' the cable taken along thelines i2-i2, I3-I3, and Il-Il, respectively, of Fig. l1;

Fig. 15 is an enlarged elevational view of the paper supply unit shownin Fig. l; 15

Fig. 16 is an end View, partially in section, of

the paper supply unit shown in Fig. 15;

Fig. 17 is an enlarged view of the commutator shown in Fig. 16, takenalong the line Il-i'i of Fig. 16; 20

Fig. 18 is a perspective view, partially in section, oi' a flierstrander showing another embodiment of the invention;

Fig. 19 is an enlarged perspective view of a portion of the apparatusshown in Fig. 18 for 25 forming the paper over the cable core;

Figs. 20 to 25, inclusive, show methods of applying one or more layersof paper over the cable core by means of the apparatus shown in Figs.

18 and 19; 30

Fig.` 26 is a view of a portion of the forming (die shown in Fig. 27;

Fig. 27 is a view of a paper forming die;

Fig. 28 is a sectional view taken along the line 28-29 of Fig. 27; 35

Figs. 29 to 31, inclusive, are views of another embodiment of the paperforming die for forming a lap in one direction;

Fig. 32 .is a view of a portion oi the die similar to that shown inFigs. 29 to 31, inclusive, for 40 forming a lap in the oppositedirection;

Fig. 33 is a section oi' a lead covered cable, partially incross-section, having longitudinally applied paper covering and a cottonstrand binding over the paper; 45

Fig..34 is a view partially in section, of another embodiment o! theinvention;

Fig. 35 is an enlarged view of means for applying a strip of paper overa cable core just prior to its entrance into an extrusion press; 50

Fig. 36 is a sectional view taken along the line 36-36 of Fig. 34;

Fig. 37 is a sectional view showing an auxiliary paper forming means andtaken along the line ll-'l of Fig. 35, and y 55 Fig. 38 is a perspectiveview of a removable segment of a cable core guide shownin Fig. 34.

Referring to the drawings in which similar parts are indicated byidentical reference numerals, a preferred embodiment of the invention(Fig. 1) comprises a rotatable core truck 40 having a supply of cottonbound cable core 4| thereon, a paper supply unit 42 having a supply ofcrinkled or crepe paper 43 thereon, a moisture proof tube 44 throughwhich the cable core 4| and the paper 43 pass, a metal extrusion press45 having a core tube 46 with a paper forming die 41 therein, and atake-up reel 48. The core truck and the paper supply unit 42 are locatedin a low humidity storage oven. The core truck 40 has a base 49 and ismounted on wheels 50. The paper supply unit 42 (Figs. 1, and `15 to 17,inclusive) comprises a main supply arbor 5| to which a metal disc 52 issecured, and having an extended shaft portion 53. The shaft portion 53is supported by a channel member and a ball bearing pillow block 55. Thepaper 43 is secured to the supply arbor 5| by means of a knurled portion56 and a clamp nut 58. A tension arm 60 is rotatably secured in a pairof lever pivot arm supports 6|. A tension paddle brake and limitindicating lever 59 is secured to the arm 60. A steel cable or rope 62,one end of which is connected to the tension arm 60 passes around apulley 63, the other end of the cable 62 isF connected to one end of apaddle tension spring 64. The tension spring 64 tends to move the paddlebrake and limit indicating lever 59 upward. It provides a denite tensionon the paper 43 as it is unreeled, and also, as described below,operates an indicator to show when the paper is about exhausted.

The channel member 54 is welded or otherwise suitably secured to a metalbase 65. An axle 66 having a pair of wheels 61 is secured to one end ofthe metal base 65. A switch 68, arranged to be operated by the tensionarm 60, is connected in series with a pad limit lamp 69 and a source of.

potential 10. The switch is adjusted to close and light the pad limitlamp 69 when the paddle brake and limit indicating lever 59 reaches apredetermined height. A brush holder 1| and a brush 12 are secured tothe shaft portion 53 and arranged to rotate with the shaft portion 53. Acommutator 13 having a plurality of contacts 14 is secured by means of acommutator holder 15 to the channel supporting member 54. One side ofeach of a plurality of pad rotation indicating lamps 16 are connected bymeans of conductors 19 througha plug 11 and a jack-box 19, to thecontacts 4 of the commutator 13. The brush 12 is connected through thesource of potential 10 to the other sides of the lamps 16. The lamps 69and 15 are located on the outer wall 19 of the low humidity storage ovenas shown in Fig. 1 and enable the operator of the extrusion press 45 todetermine whether the paper supply unit 42 is functioning properly andalso when the supply of paper 43 is becoming low. Paper tensioningfingers 80, through which the paper 43 passes, are secured to the innerside of the wall 19.

The rear end of the moisture proof tube 44 (Figs..1, 8,- 9, and 10) isslidably mountedin a A holder 8| inserted in an opening of the wall 19.

The front end of the moisture proof tube 44 is pivotally secured in aholder 82 attached to the extrusion press 45. As shown in Figs. 8 to 10,in-

clusive,l the moisture proof tube 44 has an upper 9 and 10) is providedwith hinges 83 and 84 so that the upper and lower compartments at theforward end can be opened to facilitate the insertionof the cable core4| and the paper 43 through the paper forming die 41.

The paper forming die 41 (Figs. 1 to 6, inclusive) is held in positionat the rear end thereof by the holder 82 which has a ilat surface toengageV with the at portionl 85 of the die 41, and is held in positionon the front end thereof by the conical nose 86 which engages acorresponding inner surface at the forward end of the core tube 81.

As the paper 43 and the cable core 4| pass through the die 41, the paper43 is rst formed into a U- shape by means of the lips 88 and 89 (Fig. 4)and the cable core 4| is pressed downward against the paper 43 by meansof a projection 90. The neck 9| of the die 41 is formed with a loweriin-like portion 92 and an upper fin-like portion 93,-and graduallytapers to the conical nose 86. As the paper 43 passes through the neck9| of the die 41, one edge is beneath the lower n-like portion 92 andthe other edge between the upper iin-like portion 93 and lower n-likeportion 92, as shown in Fig. 5. As the cable core 4| and paper 43 emergefrom the nose 86 of the die 41, the paper is wrapped around the cablecore as shown in Fig. 13. The die 94 shown in Fig. '7 is `similar to,though simpler in design than, the die 41 shown in Fig. 3, and may beused in some cases. The

l paper covered cable corepasses out of the core tube 81 and a sheath oflead 95 is extruded thereover by the extrusion press 45, which may be of'any suitable type well known in the art. 'I'he cable is propelledthrough the apparatus by the lead extrusion press and wound on thetake-up reel 48, which is rotatedby any suitable means, such, forexample, as the rotating floor rollers 96 (Fig. 1).

In another preferred embodiment of the invention, as shown in Figs. 18to 33, inclusive, the paper is applied over the insulated conductors asthey are formed into a cable core. The flier strander |0| shown in Fig.18 is shown and described'in greater detail in U. S. Patent 1,813,917granted to me July 7, 1931. The ier |02 is arranged to rotate. The base|03 is arranged to be held stationary within the rotating ier |02 bymeans of suitable planetary gearing (not shown).

Mounted on the base |03 are several rolls of repe paper43, a strandserving head |04, guide ngers |05, which may serve, if-necessary, toapply a tension to the paper 43, guide pulleys |06, a rst paper formingdie |01 and a second paper forming die |08. 'I'he forming dies |01 and|08 are located between a sizing die |22 which forms the individualinsulated conductors |23 into a cable core ||0, and the serving head|04. 'I'he conductors |23 are propelled from the strander.

supplies (not shown) through a positioned face plate |09 intothe sizingdie |22, forming dies |01 and |08, strand serving head 04, sizing dieII4, and then through the restl of the machine (not shown). the supplyrolls through the guide ngers |05, around the guide pulleys |06 andthroughthe forming dies |01 and |08. 'I'he forming dies |01 and 08,through which the cable core |I0 is also propelled, form the layers ofpaper around the cable core.

The serving head |04 has a cop of cotton strand ||2 mounted therein, andguide pulleys ||3 associated therewith. This arrangement applies astrand ||2 around the paper covered cable core between the serving head|04 and 'Ihe crepe paper 43 is fed from the sizing die ||4. The die ||4is mounted in a sizing die holder H5 which rotates at the same speed asthe flier |02 and the cable. As the cable core ill and the paper strips43 have a twist applied thereto between the face plate |09 and thesizing die H4, the layers of paper 43 are longitudinally spiralledaround the cable core.

'l'he forming dies |01 and |00 (Figs. 18, 19 and 29 to 31, inclusive)have a pair of forming lips ||6 and a supporting ring .||1. As shown inFig. 31, the forming lips ||6 are conical in shape to gradually reducethe diameter of and to easily form the paper covering 43. They arearranged so that when desired one layer of paper can pass around theoutside of the forming lips H6, while another layer of paper passesinside the forming lips and is being formed around the cable core. InFig. 18 there are shown three layers of paper 43 being applied aroundthe cable core, the two lower strips being led through the interior ofthe forming lips ||6 of the first and second forming dies |01 and |06,and the upper strip being fed through the space between the forming lipsH6 l and supporting ring H1 of the first forming die |01 and through theinterior of the forming lips ||6 of the second die |00, and formedaround the cable. When desired additional layers of paper may be appliedor only one or two layers can be applied. It isalso possible by the useof the die shown' in Fig. 31, with that shown in Fig. 32, to apply twolayers of paper from the same side and at the same time give themdifferent directions of lap.

In Fig. 19 are shown two layers of paper 43 being applied through dies||1 over the cable core ||0 from lone side of the cable. This results intwo layers of paper with the lap in the outer layer over the top of thelap in the inner layer. The two layers of paper could be applied fromopposite sides of the cable core (as shown in Fig. 25) with the laps inthe paper 43 on the opposite sides of the cable core. In Figs. 20 to 25,inclusive, there are shown layers of paper and strand serving beingformed over the cable core ||0, the paper forming dies and strandserving apparatus having been omitted from the drawings to simplify thedisclosure` In the embodiment shown in Figs. 20 and 2l, a single layerof paper 43 is being applied overthe cable core H0, and is bound by thestrand ||2. In the embodiment shown in Figs. 22 and 23, two layers ofpaper 43 are being applied from the same side of the cable core, theinner layer of paper being formed around the cable core I0, and theouter layer being formed over the rst layer. In the vembodiment shown inFigs. 24 and 25, two layers of paper 43 are being applied from differentsides of the cable core ||0, the inner layer being first formed aroundthe cable core ||0, and the outer layer over the first layer.

'I'he paper forming dies |01 and |08 are preferably formed with thesupporting ring ||1 in two halves (Figs. 29 and 30) to facilitate in theconstruction thereof and so that the forming lips ||6 may be readilychanged for cables of different sizes, and to rmly hold the forming lipsin the desired position.

Another type of paper formingv die ||8 found satisfactory (Fig. 27) hasa conical forming lip I |9 secured to a segment |20 (Figs. 27 and 28)Both the `segment |20 and conical forming lip ||9 are tapered as shownto gradually reduce the diameter of and facilitate forming the paperaround the cable core ||0. When two layers of paper are to be appliedthrough separate paper forming dies, an outer annular ring segment |21(Figs. 26 and 27) is employed to allow the second wrapping of paper 43to pass around the first forming die to the second forming die. In theembodiment shown the two laps of paper would be applied from oppositesides of the cable core.

In another preferred embodiment shown in Figs. 34 to 38,' inclusive, thecrepe paper 43 is applied over the cable core 4|, in the low humiditystorage room, by means of a paper forming die |30, which is similar tothe forming die 94 (Fig. '7). A cable core guide tube 13| is employed toposition the cable core 4| properly with reference to the die |30. Thecable core guide '.'ube |3| and one end of the paper forming die |30 aresecured to a forming die and cable core guide tube support |32 which isslidably secured to a v shelf |33. A second forming die support |34,also slidably secured to the shelf |33 is fastened to the other end ofthe paper forming die |30.

A cable core guide tube |35 extends into the core tube 46 of theextrusion press 45, to prevent the paper 43 from separating from thecable core 4|, as they pass through the press. The cable core guide tube|35 is fastened to the extrusion press 45 by means of a nipple |36. Acable core guide |31 ls secured to the guide tube |35. A cable coreconfining medium, which has been shown as a flexible spring |39, passesthrough a bell-mouth in the wall 19, and is secured to the paper formingdie |30 and to the cable core guide by means of a support 14|. Otherconfining mediums such as flexible tubing may be used in place of thespring |39. The flexible spring |39 prevents the paper 43 fromseparating from the cable core 4| and at the same time provides a meansfor visual inspection of the condition of the paper over the cable core.

If the paper 43 has a defective portion it can be readily detected as itpasses through the spring |39 and the defective portion can be repairedby converting the cable core guide |31 into an auxiliary die |42 (Figs.35 and 37). This is accomplished by removing a segment |43 (Fig. 38)from the cable core guide |31 and inserting in its place a conicalforming lip |44 (Fig. 37) and moving the spring support |4| away fromthe cable core guide |31, as shown in Fig. 35. A supply of calciumchloride |46 or other suitable material is preferably kept in the bottomof the box to keep the paper 43 dry. 'I'he paper 43 is led from the box|45 over the roller |41 and through the auxiliary die |42, as shown inFigs. 35 and 37. The upper portion of the guide tube |35 adjacent thedie |42 (Fig. 35) has an opening which conforms tothe projection |49 onthe segment |43. 'Ihe paper`43 is fastened to the cable core at thispoint by means of a strand |46. The auxiliary supply may be disconnectedas soon as the defective portion has been repaired, or may also be usedas a permanent forming means when the main supply unit 42 is notfunctioning. v

While the Ispring |39 has been shown connected to the cable core guide|31 by means of the spring support |4|, the core guide |31, springsupport I4I, nipple |36and guide tube |35 may be omitted, if desired,and the spring extended to the nose of the core tube 46, at which pointthe lead sheath is applied to the cable core. This form of constructionwould be employed only in it is to be understood that the invention isgeneric incharacter and is not to be construed as limited to theparticular embodiments shown. since numerous modications thereof may bemade by persons skilled in the art, without departing from the spirit ofapplicants invention, the scope of which is to be determined by theappended claims.

What is claimed is:

1. The method of forming an electric cable, which comprises applying 'astrip of dried crinkled paper longitudinally oi' a dried group ofinsulated conductors, forming the paper transversely of and over theconductors, simultaneously twisting the paper and the conductors,binding the paper covered insulated conductors, and applying aprotective covering over the strand bound paper covered conductors, eachoi these steps being carried on while excluding moisture.

. 2. The method of forming an electric cable, which comprises applying astrip of crinkled paper longitudinally of a group of insulatedconductors, forming the paper transversely ofA and over the conductors,simultaneously twisting the paper and the conductors, and applying aprotective covering of seamless metal over the strand l bound papercovered conductors whereby the conductors are protected against wrinklesformed on the interior of the covering when the cable is bent.

3. The method of making an electric cable which comprises the steps ofstoring a group of insulated conductors in a drying chamber to removemoisture thereupon, storing a supply of crimped paper tape in a dryingchamber to remove moisture thereupon, and combining the group ofinsulated conductors with the tape as a cover while withdrawing bothfrom the chamber and while excluding access of moisture.

4. The method of making an electric cable which comprises the steps ofstoring a group of insulated conductors in a drying chamber to removemoisture thereupon, storing a supply of crinkled paper tape in a dryingchamber to remove moisture thereupon, combining the group of insulatedconductors with the tape as a cover while withdrawing both from thechamber and while excluding access of moisture, and extruding aseamless-.sheath of metal over the paper while continuing the exclusionof access of moisture.

5. The method oi making an electric cable which comprises the steps ofstoring a group oi.' insulated conductors in a .drying chamber to removemoisture thereupon, storing a supply of crinkled paper tape in a dryingchamber to remove moisture thereupon, withdrawing the corductors and thetape from the chamber, and immediately forming the tape into a coverover the conductors.

6. The method or making an electric cable which comprises the steps ofstoring a group of insulated conductors in a drying chamber to removemoisture thereupon, storing a, supply of crinkled paper tape in a dryingchamber to remove moisture thereupon, withdrawing the conductors and thetape from the chamber, immediately forming the tape into a cover overthe conductorsI and then immediately extruding a seamless sheath ofmetal over the paper.

LESTER O. REICHELT.

